(582co) Wastewater Treatment in Cellulosic Biorefineries Via Bioelectrochemical Systems

Wastewater in a biochemical refinery generating alcohol fuels from biomass contain acetate and phenolic compounds which are inhibitory to fermentation organisms. In order to realize water recycle, complete removal of these substrates is important. Typical wastewater treatment processes such as anaerobic digestion cannot handle such streams easily due o their high salt content and presence of inhibitory levels of acetate, furfural, etc. Electroactive biofilms which breakdown organics to generate electrons and protons can be employed to generate hydrogen via use of electroactive hydrogen production catalysts at the cathode.

Experimental demonstration of hydrogen production from biorefinery wastewater using a microbial electrolysis cell is presented. Coulombic efficiencies over 60% were obtained. A currrent density of 7 A/m2 was also achieved using a laboratory scale device. Commercial development of such a process has significant environmental and process benefits due to the potential of generating renewable hydrogen. Preliminary results showing proof of principle will be presented.